#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>

const int BUF_SIZE = 1024;

int main(int argc, char **argv) {
    if (argc <= 2) {
        printf("usage: %s ip_address port_number backlog\n", basename(argv[0]));
        return 1;
    }
    const char *ip = argv[1];
    int port = atoi(argv[2]);

    struct sockaddr_in address;
    bzero(&address, sizeof(address));
    address.sin_family = AF_INET;
    address.sin_port = htons(port);
    inet_pton(AF_INET, ip, &address.sin_addr);

    int sockfd = socket(PF_INET, SOCK_STREAM, 0);
    assert(sockfd >= 0);

    int ret = bind(sockfd, (struct sockaddr*)&address, sizeof(address));
    assert(ret != -1);

    ret = listen(sockfd, 5);

    struct sockaddr_in client;
    socklen_t client_addrlen = sizeof(client);
    int connfd = accept(sockfd, (struct sockaddr*)&client, &client_addrlen);
    if (connfd < 0) {
        printf("errno is : %d\n", errno);
    } else {
        char buffer[BUF_SIZE];
        memset(buffer, 0, BUF_SIZE);
        ret = recv(connfd, buffer, BUF_SIZE, 0);
        printf("receive %d bytes data: %s\n", ret, buffer);

        memset(buffer, 0, BUF_SIZE);
        ret = recv(connfd, buffer, BUF_SIZE, MSG_OOB);
        printf("receive %d bytes data: %s\n", ret, buffer);

        memset(buffer, 0, BUF_SIZE);
        ret = recv(connfd, buffer, BUF_SIZE, 0);
        printf("receive %d bytes data: %s\n", ret, buffer);
        close(connfd);
    }
    close(sockfd);
    return 0;    
}  